The Effect of Acidosis on Lactate Removal by the Perfused Rat Kidney

1976 ◽  
Vol 50 (3) ◽  
pp. 185-194 ◽  
Author(s):  
J. Yudkin ◽  
R. D. Cohen
Keyword(s):  
Rat Kidney ◽  
Acid Base ◽  
Ph Values ◽  
Constant Rate ◽  
Perfused Rat Kidney ◽  
Lactate Removal ◽  
Acid Base Status ◽  
Glucose Output ◽  
Normal Acid

1. The isolated perfused kidneys of fed rats in normal acid-base status showed a constant rate of lactate removal from the perfusate between 5 and 90 min of perfusion at a perfusate pH of 7·4–7·5. 2. Lactate removal by kidneys of rats in normal acid-base status was stimulated within 30 min by a reduction in perfusate pH to 7·1–7·2, but depressed when perfusate pH was reduced further. 3. Kidneys taken from rats previously made acidotic and perfused with media of various pH values showed a progressive fall in the rate of lactate removal during the perfusion. 4. Glucose output by the kidneys of rats in normal acid—base status perfused with lactate as substrate was not affected by an alteration in perfusate pH. The kidneys of acidotic rats generally showed an increased rate of glucose output compared with those of control rats.

Expression of rat kidney anion exchanger 1 in type A intercalated cells in metabolic acidosis and alkalosis

1999 ◽  
Vol 277 (6) ◽  
pp. F841-F849 ◽  
Author(s):  
Saskia Huber ◽  
Esther Asan ◽  
Thomas Jöns ◽  
Christiane Kerscher ◽  
Bernd Püschel ◽  
...  
Keyword(s):  
Anion Exchanger ◽  
Direct Evidence ◽  
Rat Kidney ◽  
Enzyme Reaction ◽  
Type A ◽  
Mrna Levels ◽  
Intercalated Cells ◽  
Acid Base ◽  
Anion Exchanger 1 ◽  
Acid Base Status

By enzyme-linked in situ hybridization (ISH), direct evidence is provided that acid-secreting intercalated cells (type A IC) of both the cortical and medullary collecting ducts of the rat kidney selectively express the mRNA of the kidney splice variant of anion exchanger 1 (kAE1) and no detectable levels of the erythrocyte AE1 (eAE1) mRNA. Using single-cell quantification by microphotometry of ISH enzyme reaction, medullary type A IC were found to contain twofold higher kAE1 mRNA levels compared with cortical type A IC. These differences correspond to the higher intensity of immunostaining in medullary versus cortical type A IC. Chronic changes of acid-base status induced by addition of NH4Cl (acidosis) or NaHCO3 (alkalosis) to the drinking water resulted in up to 35% changes of kAE1 mRNA levels in both cortical and medullary type A IC. These experiments provide direct evidence at the cellular level of kAE1 expression in type A IC and show moderate capacity of type A IC to respond to changes of acid-base status by modulation of kAE1 mRNA levels.

scholarly journals Effects of External Acidification on the Blood Acid-Base Status and Ion Concentrations of Lamprey

1988 ◽  
Vol 136 (1) ◽  
pp. 351-361
Author(s):  
LEONA MATTSOFF ◽  
MIKKO NIKINMAA
Keyword(s):  
High Sensitivity ◽  
Co2 Concentration ◽  
Acid Base ◽  
Ion Concentrations ◽  
Ph Response ◽  
Ph Values ◽  
Blood Ph ◽  
Acid Base Status ◽  
The Difference ◽  
K Concentration

We studied the effects of acute external acidification on the acid-base status and plasma and red cell ion concentrations of lampreys. Mortality was observed within 24 h at pH5 and especially at pH4. The main reason for the high sensitivity of lampreys to acid water appears to be the large drop in blood pH: 0.6 and 0.8 units after 24 h at pH5 and pH4, respectively. The drop of plasma pH is much larger than in teleost fishes exposed to similar pH values. The difference in the plasma pH response between lampreys and teleosts probably results from the low buffering capacity of lamprey blood, since red cells cannot participate in buffering extracellular acid loads. Acidification also caused a decrease in both Na+ and C− concentrations and an elevation in K+ concentration of plasma. The drop in plasma Na+ concentration occurred faster than the drop in plasma Cl− concentration which, in turn, coincided with the decrease in total CO2 concentration of the blood.

Electrochemical heterogeneity of the cochlear endolymph: effect of acetazolamide

1984 ◽  
Vol 246 (1) ◽  
pp. F47-F53 ◽  
Author(s):  
O. Sterkers ◽  
G. Saumon ◽  
P. Tran Ba Huy ◽  
E. Ferrary ◽  
C. Amiel
Keyword(s):  
Inner Ear ◽  
Endocochlear Potential ◽  
Electrochemical Gradient ◽  
Acid Base ◽  
Basal Turn ◽  
Ph Values ◽  
Blood Ph ◽  
Acid Base Status ◽  
Electrochemical Heterogeneity ◽  
Inner Ear Fluids

The electrochemical composition of endolymph (EL) of two adjacent cochlear turns was studied in anesthetized rats. Differences in [K]EL, [Cl]EL, and endocochlear potential (EP) were found between the basal turn (165.6 +/- 3.0 mM, n = 14; 144.6 +/- 2.1 mM, n = 14;96.6 +/- 1.9 mV, n = 5, respectively) and the middle turn (155.7 +/- 2.5 mM, n = 15; 133.2 +/- 1.5 mM, n = 15; 87.0 +/- 1.6 mV, n = 6, respectively). The pH values of inner ear fluids were evaluated with 5,5-dimethyloxazolidine-2,4-dione: EL pH of either turn was not different from blood and perilymph (PL) pH. Acetazolamide (40 mg X kg body wt-1) reduced EP and [Cl]EL at each turn by about 20 and 6%, respectively, but [K]EL was unchanged. The electrochemical differences between the two turns persisted. Acetazolamide produced a 0.2-unit decrease in blood pH while the pH values of EL and PL remained unchanged. These results suggest the existence of an electrochemical gradient within EL from the base to the apex of the cochlea involving K+ and Cl- concentrations. H+ and HCO-3 do not appear to participate in this gradient, and the acid-base status in EL could be maintained both by active H+ transport into EL and by HCO-3 formation in the cochlear epithelium.

Meconium aspiration syndrome in term neonates with normal acid-base status at delivery: Is it different?

2001 ◽  
Vol 184 (7) ◽  
pp. 1422-1426 ◽  
Author(s):  
Sean C. Blackwell ◽  
Julie Moldenhauer ◽  
Sonia S. Hassan ◽  
Mark E. Redman ◽  
Jerrie S. Refuerzo ◽  
...  
Keyword(s):  
Meconium Aspiration Syndrome ◽  
Acid Base ◽  
Term Neonates ◽  
Meconium Aspiration ◽  
Acid Base Status ◽  
Normal Acid

scholarly journals THE EFFECTS OF SEASONAL VARIATIONS IN TEMPERATURE ON EXTRACELLULAR ACID-BASE STATUS IN A WILD POPULATION OF THE CRAYFISH AUSTROPOTAMOBIUS PALLIPES

1993 ◽  
Vol 181 (1) ◽  
pp. 295-311
Author(s):  
N. M. Whiteley ◽  
E. W. Taylor
Keyword(s):  
Seasonal Variations ◽  
Low Temperatures ◽  
Seasonal Changes ◽  
Wild Population ◽  
Late Summer ◽  
Co2 Solubility ◽  
Acid Base ◽  
Austropotamobius Pallipes ◽  
Ph Values ◽  
Acid Base Status

Between February 1990 and February 1991, a wild population of Austropotamobius pallipes (L.) inhabiting a large, shallow, freshwater pool in Staffordshire, central England, experienced environmental fluctuations in water temperature (1–21°C) and pH (8.2-9.5). Moulting was seasonal, with crayfish entering pre- and postmoult between May and August. Haemolymph pHa levels declined in the spring when temperatures increased from 8 to 18°C (deltapH/deltat=−0.013 pH units°C-1). This decrease was accompanied by a fall in [HCO3-] (of 4.12 mmol l-1) and [lactate] (of 4.71 mmol l-1) and a premoult elevation in PCO2 to 0.59 kPa. After ecdysis, when water temperatures and pH were at their maxima, pHa levels increased, they continued to increase as temperature fell in late summer, reaching 7.97 in intermoult crayfish at 13°C during September. This increase was accompanied by a decrease in PCO2 to 0.22 kPa at constant [HCO3-] (5–6 mmol l-1). Between September (13°C) and October (11°C) pHa fell to 7.87 with an elevation in PCO2 (of 0.18 kPa) and [lactate] (of 1.84 mmol l-1). As temperature continued to decrease (11–1°C), pHa remained unchanged despite an elevation in [HCO3-] by 2.4 mmol l-1 at constant PCO2. A mechanism accounting for the unvarying haemolymph pH values at low temperatures is proposed, stressing the importance of temperature-related seasonal changes in CO2 solubility and measured values for pK1′ in addition to adjustments in [HCO3-] and PCO2. These were apparently unaffected by changes in collecting and holding protocols.

scholarly journals Acid-Base Status Disturbances in Patients on Chronic Hemodialysis at High Altitudes

2018 ◽  
Vol 2018 ◽  
pp. 1-5 ◽  
Author(s):  
Javier Enrique Cely ◽  
Oscar G. Rocha ◽  
María J. Vargas ◽  
Rafael M. Sanabria ◽  
Leyder Corzo ◽  
...  
Keyword(s):  
Metabolic Acidosis ◽  
Metabolic Alkalosis ◽  
Base Excess ◽  
Chronic Hemodialysis ◽  
High Altitudes ◽  
Acid Base ◽  
Arterial Blood ◽  
Base Disorder ◽  
Acid Base Status ◽  
Normal Acid

Background. Acid-base disorders have been previously described in patients with chronic hemodialysis, with metabolic acidosis being the most important of them; however, little is known about the potential changes in acid-base status of patients on dialysis living at high altitudes. Methods. Cross-sectional study including 93 patients receiving chronic hemodialysis on alternate days and living in Bogotá, Colombia, at an elevation of 2,640 meters (8,661 feet) over sea level (m.o.s.l.). Measurements of pH, PaCO2, HCO3, PO2, and base excess were made on blood samples taken from the arteriovenous fistula (AVF) during the pre- and postdialysis periods in the midweek hemodialysis session. Normal values for the altitude of Bogotá were taken into consideration for the interpretation of the arterial blood gases. Results. 43% (n= 40) of patients showed predialysis normal acid-base status. The most common acid-base disorder in predialysis period was metabolic alkalosis with chronic hydrogen ion deficiency in 19,3% (n=18). Only 9,7% (n=9) had predialysis metabolic acidosis. When comparing pre- and postdialysis blood gas analysis, higher postdialysis levels of pH (7,41 versus 7,50, p<0,01), bicarbonate (21,7mmol/L versus 25,4mmol/L, p<0,01), and base excess (-2,8 versus 2,4, p<0,01) were reported, with lower levels of partial pressure of carbon dioxide (34,9 mmHg versus 32,5 mmHg, p<0,01). Conclusion. At an elevation of 2,640 m.o.s.l., a large percentage of patients are in normal acid-base status prior to the dialysis session (“predialysis period”). Metabolic alkalosis is more common than metabolic acidosis in the predialysis period when compared to previous studies. Paradoxically, despite postdialysis metabolic alkalosis, PaCO2 levels are lower than those found in the predialysis period.

scholarly journals Acid-Base Effects of a Bicarbonate-Balanced Priming Fluid during Cardiopulmonary Bypass: Comparison with Plasma-Lyte 148. A Randomised Single-Blinded Study

2008 ◽  
Vol 36 (6) ◽  
pp. 822-829 ◽  
Author(s):  
T. J. Morgan ◽  
G Power ◽  
B. Venkatesh ◽  
M. A. Jones
Keyword(s):  
Metabolic Acidosis ◽  
Cardiopulmonary Bypass ◽  
Base Excess ◽  
Strong Ion Difference ◽  
Acid Base ◽  
Elective Cardiac Surgery ◽  
Standard Base Excess ◽  
Acid Base Status ◽  
Standard Base ◽  
Normal Acid

Fluid-induced metabolic acidosis can be harmful and can complicate cardiopulmonary bypass. In an attempt to prevent this disturbance, we designed a bicarbonate-based crystalloid circuit prime balanced on physico-chemical principles with a strong ion difference of 24 mEq/l and compared its acid-base effects with those of Plasma-Lyte 148, a multiple electrolyte replacement solution containing acetate plus gluconate totalling 50 mEq/l. Twenty patients with normal acid-base status undergoing elective cardiac surgery were randomised 1:1 to a 2 litre prime of either bicarbonate-balanced fluid or Plasma-Lyte 148. With the trial fluid, metabolic acid-base status was normal following bypass initiation (standard base excess 0.1 (1.3) mEq/l, mean, SD), whereas Plasma-Lyte 148 produced a slight metabolic acidosis (standard base excess -2.2 (2.1) mEq/l). Estimated group difference after baseline adjustment was 3.6 mEq/l (95% confidence interval 2.1 to 5.1 mEq/l, P=0.0001). By late bypass, mean standard base excess in both groups was normal (0.8 (2.2) mEq/l vs. -0.8 (1.3) mEq/l, P=0.5). Strong ion gap values were unaltered with the trial fluid, but with Plasma-Lyte 148 increased significantly on bypass initiation (15.2 (2.5) mEq/l vs. 2.5 (1.5) mEq/l, P <0.0001), remaining elevated in late bypass (8.4 (3.4) mEq/l vs. 5.8 (2.4) mEq/l, P <0.05). We conclude that a bicarbonate-based crystalloid with a strong ion difference of 24 mEq/l is balanced for cardiopulmonary bypass in patients with normal acid-base status, whereas Plasma-Lyte 148 triggers a surge of unmeasured anions, persisting throughout bypass. These are likely to be gluconate and/or acetate. Whether surges of exogenous anions during bypass can be harmful requires further study.

scholarly journals Log-Jam in Acid-Base Education and Investigation: Why Make it so Difficult?

1998 ◽  
Vol 35 (1) ◽  
pp. 85-93
Author(s):  
James Hooper ◽  
William J Marshall ◽  
Arthur L Miller
Keyword(s):  
Medical Students ◽  
Acid Base ◽  
Logical Interpretation ◽  
Ph Values ◽  
Safe Management ◽  
Acid Base Status ◽  
Base Data ◽  
Base Education

Medical students frequently have difficulty in interpreting acid-base data particularly when pH values are used. The difficulty persists when students qualify and has implications for the safe management of patients who require investigation of acid-base status. Simplification of tuition is required together with a change of practice in the reporting of acid-base data by the laboratories. To improve understanding, we recommend that the teaching and reporting of acid-base status should be changed to use [H+] instead of pH, and a greater emphasis placed on the logical interpretation of primary measurements—that is [H+] and PCO2-with less reliance on derived variables.

Glutamine Production Rate and its Contribution to Urinary Ammonia in Normal Man

1982 ◽  
Vol 62 (3) ◽  
pp. 299-305 ◽  
Author(s):  
M. H. N. Golden ◽  
P. Jahoor ◽  
A. A. Jackson
Keyword(s):  
Production Rate ◽  
Ammonia Excretion ◽  
Whole Body ◽  
Acid Base ◽  
Male Adult ◽  
Body Protein ◽  
Acid Base Status ◽  
N Enrichment ◽  
Glutamine Production ◽  
Normal Acid

1. Glutamine [15N]amide was infused at a steady rate of 33.34 μmol/h into seven male adult volunteers who were in the fed state and normal acid-base status. 2. Plasma glutamine amide N enrichment and urinary ammonia N enrichment rose to a constant value within 3 h. 3. The glutamine production rate was 51.8 ± 7.9 mmol/h. 4. The total ammonia excretion rate was 0.87 mmol/h. Of this excreted ammonia 62.6 ± 9% was derived from the amide N atom of glutamine. 5. The excreted glutamine amide N (0.53 mmol/h) was only 1% of the glutamine production. If half the ammonia formed by the kidney is excreted in urine and half liberated into the renal vein in subjects with normal acid-base status [E. E. Owen & R. R. Robinson (1963) Journal of Clinical Investigation, 42, 263–276], then the kidney accounts for only 2% of glutamine disposal. 6. Whole body protein turnover, measured from the urinary [15N]ammonia enrichment, was 30.3 ± 7.7 g of N/day (2.8 g of protein day−1 kg−1).

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